According to the 14th Roman ordo, of 1241, the pope places on the emperor's head first the mitra clericalis, then the imperial diadem.
The procession was followed, inside the church, by a curious combination of ritual office and mystery play, the text of which, according to the Ordo processionis asinorum secundum Rothomagensem usum, is given in Du Cange.
When the control of the courts passed into the hands of the property equites, all who were summoned to undertake the duties of judices were called equites; the ordo judicum (the official title) and the ordo equester were regarded as identical.
We may compare the common use of the word ordo in profane writers, who refer, e.g., to the ordo senatorius, ordo equester, &c. It is true that the evidence of Tertullian does not carry us back farther than the close of the znd or opening of the 3rd century A.D.
But a little before Tertullian, Irenaeus, though he does not use the word ordo, anticipates in some measure Tertullian's abstract term, for he recognizes a magisterii locus, " a place of magistracy " or " presidency " in the church.